Thermostat diaphragm



May 31,1927. 1, ,733

P. F. DODUNSKI THERMOSTAT DIAPHRAGM Filed Auz. 29, 1925 .P; IYDodunski Patented May 31, 1927.

Parent errica I'ETEB F. DODUNSKI, O1? SOLON, OHIO.

THERMOS'IAT DIAPHRAGM.

Applicationfiled August 29, 1925. Serial No. 53,234.

The present invention relates in general to the art of thermostats and has for its object to provide a. thermostatic device having a diaphragm plate which embodies novel features of construction whereby extreme accuracy is obtainable.

Further objects of the invention are to provide a thern'iostatic device of this character which will expand and contract in a uniformmanner and will always return to its original position after expansion, which will. give accurate results, and which can be made small in size.

One particular embodiment of the invention will be shown and described in detail for illustrative purposes. although it will be understood that many modifications and changes can be made in the details of con struction Without departing from the spirit of the invention.

For a full understanding of the invention reference is to be had to the following de scription and accompanying drawings in which,

Figure 1 is a. sectional view through a thermostatic device which is constructed in accordance with the invention and has a platrality of diaphragms properly assembled to provide two fluid chambers.

Figure 2 is a top plan view of the thermostat. and Figure 3 is a sectional view through two of the diaphragm plates which have a complemental formation so that they can be assembled to provide a fluid chamber,

35 the thermostat plates being shown as sepa- .rated from each other and in a flat condition.

Corresponding and like parts are referred to in the following description and indicated on all of the views of the drawings by like reference cha acters.

The thermostatic device which is illustrated by Figure 1 of the drawings comprises two fluid chambers, A and B, which 4 are similar in construction and communicate with each other through a passage C formed in a dividing plate 1 which connects the two fluid chambers. Each of the fluid chambers is formed with complemental diaphragm plates 2 and 3, the plate 2 being provided at its periphery with aflange 4 which is folded around the edge of the plate 3 to provide a peripheral joint between the plates. The flange 4 is crimped tightly around the edge of the plate 3, and if necessary solder joint.

The diaphragm plates 2 and are circular in shape and each have a flat seat 5 at the central portion thereof. Surrounding the flat seat 5 are concentric annular corrugations 6 which have a peculiar formation which facilitates the flexing of the diaphragm plates when the thermostat device is in operation. The corrugations 6 have long walls 6 which are inclined at a comparatively small angle and short walls 6 which are inclined at a sharp angle. The long walls 6 are located at the inner sides of the corrugations, while the short walls 6* are located at the outer sides of the corruof the corrugations meet at a comparatively sharp angle and form concentric angiular ridges extending around the diaphragm plate. In a like. manner the walls of adjacent corrugations meet at a comparatively sharp angle so that there are angular valleys extending around the plate between the ridges. The long sides 6 of the corrugations are inclined outwardly from the cen ter of the plate at a. comparatively small angle to the surface of the plate, while the short sides 6" are inclined downwardly from the long sides (3 at a sharp angle.

A pair of complelneutal diaphragm plates 2 and 3 is assembled to form each of the fluid chan'ihers. The opposite seats 5 of ad jacent fluid chambers may be connected by a division plate 1 and a passage C is formed through the division plate and diaphragm plates to connect the fluid chambers. A stud 7 may be secured to the flat seat 5 at the top of the upper fluid chamber A and also to the flat seat 5 at the bottom of the lower fluid chamber B. In the present instance the upper stud 7 is shown as formed with a socket 8, while the lower stud 7 has a screw member 9 threaded therein. These studs provide means for attaching the fluid chambers to any suitable or conventional mechanism which is to be actuated by the expansion and contraction thereof.

The interior of the fluid chambers is intended to be filled with a suitable thermostatic fluid. Any suitable fluid may be employed. although it has been found that splendid results are obtained where the fluid comprises six parts of ether and one part of pure alcohol. The fluid will expand when subjected to heat and the expansion of the fluid in the chambers will force the diaphragin plates of each fluid chamber apart. Similarly, the fluid will contract when it is cooled and the diaphragm plates will then move toward each other. The peculiar ton mation of the corrugations in the diaphragm plates facilitates the expansion and c(.mti'action thereof and enables great accuracy to be obtained. The diaphragm plates ma he formed ot' any suitable material. although it may be mentioned that good results may be obtained where theplates are formed of hard brass having a thicknes of .005 of an l. A thermostat; including a pair of circular dia Jhraa'm )lates havin s laced central a. if:

closed chamber, each of the diaphragm plates being "formed with concentric annular corrugations having tlat aides arranged in an angular relation to provide sharp ridges and angular valleys, one side of each of the cor rngations being longer than the. other side and the short side being arranged at an angle to the direction of movement of the plate. i

2. A thermostat diaphragm plate constructed of hard brass and termed with a central flat seat and annular corrugations havingsulJstantialtY flat sides both oi which are arranged diagonally to the horizontal plane ot the plate to provide sharp ridges and angular valleys. one side of each of the corrugations being longer than the other side and the lone side beingarranged at a smaller angle to the plane of the plate than the short side. i

In testimony whereof I atlix my signa ture.

rn'rna r. noDUits r. 

